Why not working? Solved

Question

https://code.sololearn.com/WpVQUMLWGSY9/?ref=app

Answer 1

thank you very much

Answer 2

It seems like the html element hasn't loaded when the function tries to access the element.
This looks like a failure of sololearn as the js should always be implemented at the end of the file.

Move all the code from the js section to your script tag in the html section.
Also you have to change the position of the button to relative as top/Left Properity dont work on static elements.
Then it works. Nice Idea :)